Livlprovement



` UNITED STATES PATENT OEEICE.

ORRIN NEVTON, OF PITTSBURG, PENNSYLVANIA. I

IMPROVEMENT !N MAKING `SHEET-METAL CAPS, 80C.

Specification forming part of Letters Patent No. 28,397, dated May 22,1860.

To all whom it may concern:

Be it known that I, ORRTN NEWTON, of Pittsburg, in the county ofAllegheny and State of Pennsylvania, have invented a new and usefulImprovement in the Manufacture of Seamless Metallic Gaps and Boxes, andI do hereby declare the following to be a full, clear, and exactdescription thereof.

The special object of my improvement is to make caps (suitable forsealing the mouths of jars used for preservin g fruits and vegetables)of sheet-tin or tinned iron in one piece, so as to have no joints, thusinsuring their being perfectly air-tight, and at the same time to makethe sides of the cap perfectly smooth and free from wrinkles, asotherwise they will not iit on the neck of the jar or can sufficientlyclose to form an air-tight joint.

My improvement is also applicable to the manufacture of boxes and capsof various kinds, as it produces an article of seamless boxes and caps7having a smoothness and iinish which cannot be given by any otherprocess with which I am acquainted.

I am aware that a rough article of tin caps has been made by turning upthe edge of a disk of tin by means of a stamp; but by this process theedge formed is very shallow, and is full of currugations, which renderit entirely unfit for the purpose named, or for any use where neatnessof finish is desirable.

To enable others skilled in the art to make use of my improved mode ofmanufacturing metallic caps, I will proceed to describe it, referring tothe annexed drawings, forming part of this specification, in whichdFigure lis a sectional perspective representation of the die and punchused for the first process of turning up the edge of the metallic disk,showing the disk between the punch and die after being operated upon,and

by dotted lines the position of the disk before the descent of thepunch. Fig. 2 is a sectional perspective representation of the die andpunch employed for finishing the cap, showing the cap in place after theoperation is finished and before it is discharged from the die, and bydotted lines the position of the partlynished disk before the descentofthe punch. Fig. 3 represents a iinished cap. Fig. 4 represents acircular disk of tin from which the cap is to be made.

My improved method of making metallic caps consists of the use of a dieor succession of dies, the cavity of eachbeing of smaller diameter thanthe one previously used, and the mouth of eachbeing of the diameter ofthe disk or blank, or of the unfinished cap to be passed through it, andrapidly diminishing for part of its depth, and thence to the bottom ofthe die, preserving the same diameter (if the cap is to have parallelsides) or tapering at the same angle to its axis that it is desired togive to the sides of the finished cap, and the use with such a die ordies of a punch or plunger of the same shape as the lower part of itsdie and of the same diameter less twice the thickness of the metallicdisk or cap to be operated upon by it, so that when the disk is forcedby the plunger into the lower part of the die the plunger and disk willoccupy the entire diameter of the die.

In the drawings, Fig. l, a is the diein which the first operation ofturning the edge of the disk is to be performed. It is an annular pieceof steel highly polished on its inner face. The diameter of the cavityof the die c at its mouth a; x, Fig. l, is equal to the diameter of theplane metallic circular disk, Fig. 4, which is to be operated upon inthis die, the mouth of the die being so constructed that the disk willrest in it, perfectly level, in a little groove made for that purpose,as seen in Fig. 1. `The diameter of the cavity of the die thence rapidlydiminishes, as seen in Fig. 1, so that in about one-quarter of an inchin depth the diameter will be reduced a little more than half an inch,or over one quarter of an inch all round. lIhis contraction of the diecom mences abruptly at the bottom of the shallow groove inv which thedisk is to rest; but as it approaches the point of greatest contractionat y the face of the die is curved so as not to present a sharp angle aty. From the point y to the bottom of the die the cavity is of uniformdiameter throughout, and of a depth somewhat greater than the depth ofside to be i turned up around the disk by Jthis die. The punch orplunger b is a cylindrical block of steel of uniform diameter, polished`on its under side, which is a plain surface, and also all around. Theunder edge of this plunger is rounded olf, as seen at e, Fig. 1, so thatit will bend but not crease the disk at the point Where its edge isturned up. The plunger b is thicker than the depth of the die c, so thatit will pass through the die far enough to deliver the disk withoutbecoming itself unseated. Care must be taken to have the plunger of theright diameter, which is just the diameter of the lower or smallest partof the die, less twice the thickness of the metallic disk from which thecaps are to be made, as will be seen by examining the drawings, Fig. 1.The plunger has a handle, c, exactly concentric with the axis of theplunger b, so that when the die is set in a suitable machine the`plunger may be inserted into a socket of the machine and fastenedimmediately over and concentrically with the cavity of the die. The dieis stationary, and is placed in a horizontal bed, and the plunger-sockethaving a vertical motion up and down, causes the plunger to enter thedie with its axis in the exact center of the die, so that the sides ofthe plunger do not come in contact with the face of the die, but leave aspace between them all round equal to the thickness of the metal usedfor making the caps. The stroke of the plunger must be exactly in theline of the axis of the die, and the length of the stroke such that theupstroke will raise the plunger out of the die and the downstroke willdeliver the cap, but not cause the plunger to pass entirely below theunder side of the die. rIhe die-bed of the machine on which the die isset must have an opening at least as large as the smaller diameter ofthe die to allow the cap to pass through and away from the machine. Ifit is desired to turn down the disk to a considerable depth, as inmaking a box, a succession of dies `and punches are used similarlyconstructed to those shown in Fig. 1, each die being smaller than thepreceding one of the series, the diameter .fr x at the mouth of eachintermediate die being equal to the diameter of the lower part of thedie next preceding it in the series, and each succeeding die must haveless difference in diameter between its mouth, andits lower part thanthe preceding one in the series had, because the more frequently theedge of the disk is subjected to the contracting power of the dies theless easy it becomes to contract it still further, and therefore it mustbe done by degrees; otherwise the metal may tear instead of drawing outsmoothly and evenly 5 but in turning up an edge of less than half aninch in a disk of about two inches in diameter two operations only arenecessary, and having been turned up with a rounding edge by the die andplunger shown in Fig. 1, the cap is placed in the nishing die shown inFig. 2.

rIhe finishing-die d and plunger e, Fig. 2, are constructed like thoseshown in Fig. 1, excepting in the 'Ollowing particulars: The diameter ofthe mouth of the die x x, Fig. 2, is, of course, less than the diameterof the mouth a: x of the die, Fig. 1, the diameter of the mouth of thefinishing-die d being equal to the smallest diameter of the cavity ofthe predie previously used, for the reason before stated. The lower edgeof the plunger e is not rounded like the plungers used with the rst orintermediate dies, the lower face of the die and its sides meeting atright angles, so as to give a sharply-defined edge to the cap whenfinished. The diameter of the plunger'e, like that of the plunger b,Fig. 1, is such as to fit closely in the lower part of the cavity of thedie when the cap is forced into it.

I have described the dies and plungers having sides at right angles tothe face of the plunger, which is the case when a cylindrical cap or boxis to be made 5 but when the sides of the cap or box are designed toconverge, the sides of the plunger and of the inner face of each die inthe series have the same angle to their axis as the sides of thefinished cap are to have to its axis.

The mode of making caps or boxes out of metallic disks by myprocess isas follows: A disk of metal, f, Figa, of the diameter of the mouth ofthe first die, u, Fig. 1, is placed horizontally in the mouth of thedie, (the plunger b being raised out of the die.) This disk rests in thegroove m x, and cannot tilt on account of the rapid contraction of thecavity of the die below the points x x. The disk f is first lubricatedby dipping it in soap-suds or oil.

The piston or plunger c then descends and f forces the disk down intothe cavity of the die, drawing out the edges of the disk radi-v ally andcontracting it circumferentially, until the entire disk is forced intothe die, where it assumes the shape shown in Fig. 1. The plunger, stillfurther descending, delivers the cap underneath, and then the plungerreturns, ready to operate on another disk. Y The disk f, with its sidesturned upward all round for a short distance within its circumference,is then (if it is desired to make the sides of any considerable depth)passed through a succession of dies, each of which reduces its diameterand elongates the sides, drawing them out at right angles (or otherrequired angle) t0 the top of the cap. It is then placed in thefinishing-die, the edge of the unnished cap resting in the mouth x x ofthe die, as seen by dotted lines in Fig..2, and on the descent of theplunger the sides of the disk are still farther drawn out, and thenished cap, shaped .y

one, the mouth of each die being of the diameter of the blank orunfinished cap to loe op erated upon, and the diameter of the cavityrapidly diminishing through part of its depth and thence to the bottoni,having the same angle to the axis of the die as the sides of theiinished cap are designed to present to its axis, with a plunger orplungers iittng into said die of the same shape as the lower part of thedies7 and of such diameter as together with the metal of the disk or eapto fill up the entire diameter of the dies, for the purpose of drawingout radially and contracting ciroumferentially the edge of metallicdisks, so as to form seamless caps or boxes, substantially in the mannerdescribed.

In testimony WhereofI, the said ORRIN NEW- TON, have hereunto set myhand.

ORRIN NEXVTON. Witnesses:

MARTIN G. GUsHiNG, A. O. BAKEWELL.

